Equilibrator for airships.



D. B. ELLSWORTH.

EQUILIBRATOR FOR AIRSHIPS.

APPLICATION FILED DEC. 13, 1910.

Patented Apr. 23; 1912.

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D. B. ELLSWORTH.

EQUILIBRATOR FOR AIRSHIPS.

APPLIOATION TILED D3013, 1910.

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EQUILIBRATOB. FOR AIRSHIPS.

APPLICATION FILED 11110.13, 1910.

Patented Apr. 23, 1912.

5 SHEETS-SHEET 3.

- INVENTOR,

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D. B. ELLSWORTH.

EQUILIBRATOR FOR AIRSHIPS. APPLICATION 11.39 DEO.13,1910.

Patented Apr. 23, 1912.

5 SHEETS-SHEET 4.

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,4 TTOR/VEYS D. B. ELLSWORTH.

EQUILIBRATOR FOR AIRSHIPS.

I APPLICATION FILED DEG. 13, l910. 1,024,39 Patented Apr. 23, 1912.

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OFFICE.

DIGH TON B. ELLSWOR TH, O F PORTLAND, OREGON, ASSIGNOR OF'ONE-THIRD TO E. HOUSTON AND ONE-THIRD TO H. L. LANE, PQRTLAND, OREGON.

momnmroa FOR amsmrs.

Application filed December 13, 1910. Serial No. 597,099.

'mechanism, so designed as to use electrical energy in combination with the force of gravity, to impart a reciprocating motion to automatically operate the balancing mechanism of an aeroplane, or other heavier-thanair air craft, and my invention has for its object to obtain an automatic balancing mechanism of the type described.

It is also my object to obtain a device .which will. operate the balancing mechanism of an airship to theproper degree for correcting any angle of inclination from the horizontal, and to reduce this degree in direct proportion as the airship approaches the horizontal. And itis my 'further object to so arrange my device thatthe operator may control the airship without rendering my device inoperative, andthat the operator may furthermore incline the airship at an angle from the horizontal and my device will maintain said angle.

In the accompanying drawings: Flgure ,1 is a partial front elevation and perspective of an aeroplane embodying my invention. Fig. 2 is a plan View of my device; Fig. 3 is a. fragmental view of the worm gear; Figs. 4, 5 and .6 are views showing that part containing the make-andbreak circuit system, and Fig. 7 isa side ele-, I vation of the magnet clutch wheel, showlng 10 the radial arrangementof the magnets on one side of said wheel, and showlng in I dotted lines the arrangement of the magnets on the opposite side; Figs. 8, 9, 10 and 11 are diagrammatic front elevations of an aeroplane, showing the. ailerons at the tips of the wings, and only that part of my device which contains the make-and-break system, illustrating the action of my device while bringing the aeroplane from an intions.

A clination back to the horizontal.- Fig.12

is similar to-Fig. 4 but illustrating another embodiment of the invention; and Fig. 13, a slde elevation of an aeroplane showing Patented Apr. 23, 1912.

particularly the second embodiment of the invention as applied to the fore and aft balancing mechanism.

The equilibrator (see Figs. 1 and 2) takes its power from the engine 1, of the aeroplane through a train of gears 3 terminating in a bevel pinion a, in mesh with two bevel wheels band 0 for the lateral balance machine.v For the longitudinal balance machine which is shown in dotted lines in Fig. 1' and also in Fig. 13 a similar train of gears 3, a, 0 is provided.

In the balance machine shown in'Fig. 2, the-bevel pinion, a, drives in opposite directions a pair'of bevel wheels I? and 0, runnet. Wheel (Z, keyed to the shaft 0 in such a manner as to rotate with the shaft and yet allow lateral movement of the magnet wheel upon the shaft. .Thebearings m for the shaft 0 are attached to the frame of the aeroplane. The magnet wheel d (see also Fig. 7) has two sets of magnets 03 and (Z facing, respectively, the-two bevel gears 72 and 0, thelatter acting as armatures to the respective magnets. The magnets are suitably connected to three collector rings :0, y,

and 2, shown situated on the surface of the magnet wheel. The bevel gears or armatures will be hereinafter called, respectively,

the right-hand armature, c and the left; hand armature b, and it is understood that, they constantly revolve in opposite direc- The magnet wheel d-an'd its armatures I) and c clutch.

Onthe shaft 0 Figs. 1, 2 and 3 is situated a spool e, actuating the cords 4 (shown in form a reversible magnetic dot-and-dash line in Fig. 1) which operate the ailerons 5, and beyond this spool, on said shaft 0, is a worm f shown in Fig. 8, driving a worm wheel f on a shaft p which lat: ter is at right angles to the clutch shaft 0. Upon said shaft go (see Figs. 4, 5' and 6) are a block it and a pendulum g loosely attached and the block is adjustable relative to the worm wheel f, as hereinafter described, but

may be rigidly attached to and rotatable.

tively in the center, on the right and on the left. The central terminal 7; is connectedthrough conductor to a battery or generator is (see also Fig. 2) which is in turn connected to the brush g on the central collector ring y of the magnet wheel (1. This ring is connected vto both series of magnets d and (Z and the latter are respectively connected tothe right and left hand collector rings wand z, the right hand collector ring brush 2 being electrically connected through conductor 7' to the right hand terminal i on the block 71., and the left hand collector ring brush :20 being electrically connected through conductor j to the left hand terminal 2' onv the block it. It will now be seen that both the right and left hand magnet circuits are broken only at the contact block. 1.

The pendulum g is hung free on the block shaft p in front of the block h. The central terminal 2' terminates in two contact points,'one on either side of the pendulum, while the left and right hand terminals 2" and i are each one point and are arranged in such a manner that any relative movement between the block and the pendulum will cause the latter to close the circuit, allowing the current from the battery to energize either the right or left hand magnet, which will be attracted to its respective armature b or c; which attraction will carry the wheel along the shaft 0 into contact with the armature, and as the armature is constantly rotating, cause the wheel to be driven by and revolve with it; but as the magnet wheel d is keyed to the shaft 0, the latter will revolve also, turning the spool e, which inclines the ailerons 5. This shaft 0: terminating in the worm f of the worm wheel f, will cause said worm wheel to rotate on the block shaft 19, carrying the block it backto the horizontal, thus'breaking the circuit, regardless of the inclination of the aeroplane as a whole. This prevents any further revolving of the magnet wheel (Z, and a consequent increase of the inclination of the aileronsover what is desirable before the aeroplane, as a whole, -could be brought back.

to the horizontal; it being necessary to incline the ailerons only a slight degree'for a slight inclination Yet if greater inclination should be attained, greater movement of the'ailerons must take place to counteract it. It is also necessary, as the machine approaches the horizontal, to decrease the angle of inclination of the ailerons.

Turning now to Figs. 8, 9, 10 and 11, which are diagrammatic front elevations of an aeroplane, showing the ailerons 5, 5 at the tips of the wings, and an enlarged view of the contact block h, pendulum g and terminals z" and i the rest of the machine not being shown. These figures illustrate a series of positions representing the movement of an aeroplane from an inclination to the horizontal. In Fig. 8 the aeroplane is tipped at an angle to the horizontal, and the inclining of the block it has allowed the pendulum g to make the contact at the right hand terminal 2' Comparing this view with Fig. 2, the closing of the circuit of the right hand terminal 2' completes the circuit through conductor j of the right hand magnet wheel (P, which latter then is attracted to the right hand armature o, and revolves with it, turning the shaft 0, and subsequently the spool e, the worm f and the worm wheel-f. In Fig. 9 the result of this action is shown, the ailerons 5 having been set to level the aeroplane, and the worm wheel and block it brought back to the horizontal, the contact being broken.

It Will be seen that only sufiicient inclination of the ailerons is given for any degree of inclination of the aeroplane, as a slight inclination of the aeroplane would re quire only a partial revolution of the mag-' net wheel to break the circuit of the block, which partial revolution would set the ailerons at a slight angle; whereas a greater inclination of the aeroplane would require a greater number of revolutions of the magnet wheel to break the circuit at the block, which would incline the ailerons to a greater degree.

The action of the air upon the ailerons of the aeroplane, when arranged as shown in Fig. 9, tends to bring the aeroplane back to the horizontal, when a condition is met as illustrated in Fig. 10. The block it, which was horizontal in Fig. 9, is now tipped to the left, owing to the fact that the aeroplane previously inclined to the right is now more nearly horizontal, and contact is made with the left-hand terminal 2" which energizes the left-hand magnet circuit through conductor y" attracting the magnet to the left hand armature b, which turns the magnet wheel (Z in the opposite direction to its former rotation. This opposite rotation of the magnet wheel turns the shaft 0 and spool e in the opposite direction to that of their former rotation, bringing the ailerons opposite rotation of the worm wheel and ductor j and stopped the action. A furcontact block has broken the circuit of con- 1 ther movement of the aeroplane toward the horizontal will repeat this action last dezontal position, and the contact block his also brought back to the horizontal in-its relation to the pendulum g and the aeroplane. A movement of the aeroplane to the left would reverse the whole process just described, starting the movement caused byv the closing of the left hand circuit through conductor 9'' and returning with a series of slight movements caused by the closing of the righthand circuit of conductor j. If, during the return of the aeroplane to the horizontal, an outside vforce should incline it to a greater angle than formerly, the contact block 'h'carried with the aeroplane would close the circuit to set the ailerons at a greater angle. It is seen that at all times the machine has set the ailerons to their correct amount of inclination to give their proper efliciency at the particular angle at which the aeroplane is found. As this angle is changed by the action of the ailerons on the 'air, the machine constantly 1 changes the amount of inclination of the ailerons to meet the 'new condition.

Heretofore the block 71,- has been considered as rigidly attached to the worm .wheel f. The actual attachment is illustrated specifically inFig. 6, and consists of a pair of cords 1- and s, aflixed to a point on the block 71. and directly over the shaft and running throughpulleys'w, w, in the cire cumference ,of the worm wheel f. Passing from the pulleys these cords (1" and 8) converge at a common point g on the line of the block shaft p. Passing from this point the cords (r and s extend to the base of the steering wheel, where (as 7' and s they separate from a common point 9 and are attached to the arms of a lever t, whose fulcrum 'is at one end of a shaft, passing through the post to the steering wheel, the

other end of this shaft terminating in an indicator arrow 1), which registers on a :curved scale a on the wheel.

These. cords are of equal length, and when the indicator 1) at the top of the steering wheel registers zero,vthe tips of the lever t at the base of the steering wheel will'be equi-distant-from* the separating point .9 thus 1' and s will The cords r and s between the two points are constantly equal, being par.-

allel; therefore, under this condition thecords r plusr and 8 plus 8 must be equal.

'Letus consider that the worm wheel 7 is ,the base of aright cone, whose axis is the block shaft '7), and whose apex is the common point (7. It is then evident that the cords rand s will lie on the face of this,

I imaginary cone, and as the distance from which case the'wheel may revolve on its shaft without changing the length of these .cords 1- and s,.and as these cords remain constantly equal, the block it carried by the cords 1- and 3 will revolve with the wheel f.

If the operator should desire to tip' his aeroplane, he moves the indicator 11 on the steering wheel to the right or left, thus changing the lengths of the cords 1' and s at the base .of the steering wheel. As the cords r and s between the points 9 and Q areconstantly equal, and as the' cords 'r' and s between the converging point q and the pulleys w are constantly equal, this difference must be made up by the cords r and s between the pulleys "w and the point q on the block it. If the operator moves his indicator '0 so as to lengthen the'distance 1, between the right hand arm of the lever t and the point 9 the block 72, will be moved to the right as the cord r on this side will be shortened. This changes the relation of the block b to the wheel f, at the same time throwing the block b out of the horizontal, causing the pendulum g to close the contact at, i on the right handside, which starts 1 the action described for inclining the-ailerons; but the aeroplane is level, and the block is at an angle to the right of the hori- 'zontal, therefore at-the end of action, when the block comes to rest at the horizontal, the

aeroplane will be at an angle to the left of thehorizontal and the equilibrator will hold the aeroplane at this angle, in the same manner that it normally holds it horizontally.

Upon the operator returning the indicator '22 to zero, the' action is reversed, and

-when the block it comes to rest at the horizontal again, the aeroplane will also be hori- The action of elevating rudders Fig. 13 is similar,longitudinally, to the lateral ,action of the ailerons. I realize that many forms of the device placed convenient to the seat 6 (shown in'Fig. 1) may be arranged to operate th'e'control cords 1' and s;

In' thelateral machine the worm wheel f, operated by the clutch shaft 0, rides on the block shaft, p, said shaft 79 beingat right angles to the clutch shaft 0 but the wheel f may be operated by a spiral or friction drive in which case theshaft 0 would be parallel with shaft p. The same arrangement may alsobeused for the longitudinal the block shaft p is paralled to the magnet.

wheel shaft and its accompanying wheel f is operated by a spur gear. Any other suitable mechanical appliance, such as a chain or friction drive from the shaft 0 might however be used. The elevating rudders are connected through cords 12 with the spool e. Cords R and S attached to the contact block run over pulleys in wheel f to either end of lever t mounted on the same shaft as the indicator '0 near the steering wheel in the same manner as has been described in connection with the lateral ma chine.

The operator may set his elevating indicator o similarly to the lateral indicator at an angle, and the equilibrator will tip the elevating rudders, and, without his assistance, maintain this angle until he desires to change it.

In descending the elevating indicator is set to the desired angle, and the equilibrator will prevent the aeroplane from descending at a greater angle than desired, and upon approaching the earth, the operator may gradually reduce this angle, alighting with no danger of a violent impact.

The make-and-break device is similar on both machines and I realize that so many forms of electrical make and-break devices, actuated by the force of gravity, may be arranged," that I do not deem it necessary to illustrate or describe any other than the simple form shown in Fig. 4, as the details are self suggestive to any skilled mechanic.

I claim 1. In an aeroplane propelled by a motor,

I the combination with a magnetic clutch comprising a shaft; a magnet wheel slidably keyed to said shaft and two oppositely rotating circular armatures, said armatures actuated by the propelling motor and running loose on said shaft; of a spool rigidly mounted on said clutch shaft, and means for balancing the aeroplane by connections to said spool; a block wheel rotatable on a stationary shaft parallel to the clutch shaft; means rotating the block wheel by the rotation of said clutch shaft; and a block and a pendulum independently rotatable on the stationary shaft.

v 2. In an aeroplane propelled by a motor, the combination with a magnetic clutch comprising a shaft; a magnet wheel, slidably keyed to said shaft and two oppositely rotating circular armatures; said armatures actuated by the propelling motor and running loose on said shaft, of a spool rigidly mounted on said clutch shaft; and means for balancing the aeroplane by connections to said spool; a block wheel rotatable on a stationary shaft at right angles to the clutch shaft; means rotating the block wheel by the rotation of said clutch shaft; and a block and a pendulum independently rotatable on the stationary shaft.

3. In an aeroplane propelled by a motor, the combination with a magnetic clutch comprising a shaft; a magnet wheel slidably keyed to said shaft and two oppositely rotating circular armatures, normally running loose on said shaft, said magnet wheel consisting of two sets of magnets radially arranged on either sideof the wheel and re- ,spectively connected with collector rings and a source of electric energy; of a spool; a block wheel rotatable on a stationary shaft; means rotating the block wheel by the rotation of said clutch shaft; a block rotatable on the stationary shaft and normally at tached to said block wheel, electric terminals on said block, a' circuit including-said terminals, the electromagnets of said clutch and a source of electrical energy; and a pendulum rotatable on the stationary shaftmounted between said terminals and adapted to make or break the contact.

4. In an aeroplane propelled by a motor, 4

the combination with a magnetic clutch comprising a shaft,amagnet wheel, slidably keyed to said shaft and two oppositely rotating circular armatures, said armatures actuated by the propelling motor and running loose on said shaft; of a spool rigidly mounted on said clutch shaft; movable of said spool for balancing the aeroplane;

wings connected to, and adjusted by means a block wheel rotatable on a stationary shaft; means rotating the block wheel by rotation of said clutch shaft; a blockrotatable on the stationary shaft and normally attached to said block wheel; electric terminals on said block, a circuit including said terminals, the electro-magnets of said clutch, a source of electrical energy; and 'apendulum rotatable on the stationary shaft, mounted between said'terminals and adapted to make or break the contact.

5. In an aeroplane propelled by a motor, the combination with a magnetic clutch and a shaft on which it is mounted, of a spool rigidly mounted on said clutch shaft; a block wheel rotatable on a stationary shaft; means rotating the block wheel by the rotation of said clutch shaft; a block rotatable on the stationary shaft; means for adjusting the relation of said block to the block Wheel; electric -terminals on said block; and a pendulum rotatableon the stationary shaft mounted between said terminals and adapted to make or break the contact.

6. In an aeroplane propelled by a motor,

the combination with a magnetic clutch and a shaft on which it is mounted; of a spool rigidly mounted on, said clutch shaft;

- a block Wheel rotatable on a stationary shaft; means rotating the block wheel by the rotation of said clutch shaft; a block rotatable on the stationary shaft; means for adjusting the relation of said block to the block wheel, consisting of a lever on said block, cords running from said block lever through pulleys on the circumference of th block wheel to a common point in alinement with the block shaft, continuing throu h said point to connections within reach of t e operator, electric terminals on said block; and a pendulum rotatable on the stationary shaft mounted between said terminals and. adapted to make or break the contact.

7. In an aeroplane propelled by a motor, the combination with a magnetic clutch and a shaft on which it is mounted, of a spool rigidly mounted on said clutch shaft; ablock wheel rotatable on a stationary shaft; means rotating the block wheel by the rotation of said clutch. shaft; a block rotatable on the sta-.

tionary shaft; means for rotating said block by the rotation of the block wheel; means for adjusting the relative positionsof said block and said block wheel, consisting of a lever on said block, cords running from said block 'lever through pulleys on the circumference of the block wheel to a common point in alinement with the block ,shaft, continuing through said point to connections within reach of the operator; electric terminals in two sets on said block, a circuit including said terminals, the electro-magnets of said clutch and a source of electrical energy;

and a pendulum rotatable on the stationary shaft mountedbetween said sets of terminals and adapted to make contact with either of said contact points, or to break the contact.

8. In an aeroplane propelled by a motor, the combination with. a magnetic clutch and a -shaft-on which it is mounted; of a i spool rigidly mounted on said clutch shaft;

i a block wheel, rotatable on a stationary a block wheel rotatable on a stationary shaft; means rotating the block wheel by the rotation of said clutch shaft; a block rotatable on the stationary shaft; electric termi-- nals in two sets on said block, and a pendulum rotatable on the stationary sh aft mounted between said sets of terminals so that movement of the block in relation to the pendulum would connect one set of terminals.

9. In an aeroplane propelled by a motor, the combination with a magnetic clutch and a shaft on which it is mounted, of a spool rigidly mounted on said clutch shaft;

shaft; means rotating the block wheel by the rotation of said clutch shaft; a block balancing the aeroplane transversely and longitudinally respectively by connections to said rotatable spools, a'rotata-ble block wheel on each of two stationary shafts; means rotating the block wheels by the rotation of said clutch shafts respectively; and a block and pendulum for making or breaking contacts independently rotatable on each of the stationary shafts.

11. In an aeroplane propelled by a motor,

the combination wit-h a pair of magnetic clutches, each clutch comprising a shaft, a

magnet wheel slidably keyed to said shaft and two oppositely rotating circular arniatures actuated by the propelling motor and normally running loose on said shaft; of a,-

spool rigidly mounted on each of said clutch shafts; a set of movable wings respectively connected by means of cords to each of said spools and adjusted by the spools for balancing the aeroplane transversely and longi tudinally respectively; a rotatable. block wheel; on each of two stationary shafts;

means rotating the block Wheel by the rotation of said clutch shafts'respectively; a

rotatable block on each of the stationary shafts and normally attached to each of said i block "wheels; electric terminals on said blocks, a circuit including said terminals, the electromagnets of said clutches, and source of electrical energy; and a pendulum for making and breaking contacts loosely mounted on each of the stationary shafts, hung between said terminals.

12. In an aeroplane propelled by a motor, the combination with a pair of magnetic clutches, each clutch comprising a shaft, a

magnet wheel slidably. keyed to said shaft and two oppositely rotating circular armatures, said magnet wheel consisting of two sets of magnets radially arranged on either side of the wheel and respectively connected with collector rings and a source of electric energy, of a spool rigidly mounted on each of said clutch shafts; and meansfor balancing the aeroplane transversely and longitudinally respectively "by connections to said rotatable spools; a rotatable block wheel on each of two stationary shafts; means rotating the block wheels by the rotation of said clutch shafts respectively; and a block and pendulum for making or breaking contacts independently rotatable on each of the stationary shafts.

13. In an aeroplane propelled by a motor, the combination with a pair of magnetic clutches each clutch comprising a shaft, a magnet wheel slidably keyed to said shaft and two oppositely rotating circular armatures, said magnet wheel consisting of two sets of magnets radially arranged on either side of the wheel and respectively connected with collector rings; of a spool rigidly mounted on each of said clutch shafts, and means for balancing the aeroplane transversely and longitudinally respectively by connections to said rotatable spools; a rotatable block wheel on each of two stationary shafts; means rotating the block wheels by the rotation of said clutch shafts respec tively; a blockrotatable on each of the stationary shafts; electric terminals in two sets on each of said blocks, and means for connecting either set of terminals by the force of gravity working on a inovableconductor.

14. In an aeroplane propelled by a motor, the combination with a pair of magnetic clutches, each clutch having a shaft on which it is mounted, each shaft having a spool, of a rotatable block wheel on each of two stationary shafts; means rotating the block wheels by the rotation of .said

" clutch shafts respectively, a rotatable block on each of the stationary shafts, and nor-' mally attached to each of said block wheels;

electric terminals on said blocks, circuitsineluding said terminals, the electro-magnets of said clutches and asource of electrical energy; and'a pendulumrotatable on the stationary shafts mounted between said terminals.

15. In an aeroplane propelled by a motor, the combination with a pair of magnetic clutches, each clutch having a shaft on which it is mounted, each shaft having a spool rigidly mounted thereon; of a rotatable block wheel on each of two stationary shafts; means rotating the block wheels by the rotation of said clutch shafts, a block rotatable on each of the stationary shafts; and normally attached to said block wheel;

means for adjusting the-relative positions of said blocks and said blockwheels, consisting of a lever on each block, cords running from said block levers through pulleys on the 'circumference of the block wheels to common mounted between said sets of terminals, so that movement of each block inrelation to its pendulum would connect one set. of ter- .clutches, each having a shaft on' which it is mounted; eachclutch comprising a magnet wheel and two oppositely rotating circular armatures, said armatures actuated by the propelling motor; each of said magnet wheels consisting of two sets of magnets radiallyarranged on either side of the wheel and respectively connected with collector rings and a source of electric energy; of a spool mounted on each of said-clutch shafts and rotatable therewith; and means for balancing the aeroplane by connections to said rotatable spools; a pair of block wheels each rotatable on a stationary shaft; means rotating each block wheel by the rotation of its respective clutchshaft; a block rotatable on each stationary shaft; means for rotating each block by the rotation of its respective block wheel; means for adjusting the relative position of each block and block wheel, consisting of a lever on each block,-

cords running from said block levers through pulleys on the circumference of the block wheels to a common point in alinement with the block shafts respectively, continuing through said points "to connections within reach of the operator; electric termi: nals in two sets on each of said blocks circuits including said terminals, the electromagnets of said respective clutches and said source of electrical energy; and a rotatable pendulum on each stationary shaft mounted between said sets of terminals, so that movement of each block in relation to its pendulum would connect one set of terminals.

17 In an aeroplane propelled by a motor, the combination with a pair of magnetic clutches, each clutch having a shaft on which it is mounted, each clutchcomprising a magnet Wheel and two oppositely rotating circular armatures, said armatures actuated by the propelling motor, each of said magnet wheels consisting of two sets of magnets radially arranged on either side of the wheel and respectively connected with collector rings and a source of electric energy, of a spool mounted on each of said clutch shafts and rotatable therewith; and means for balancing the aeroplane by connections to said rotatable spools; a pair of block wheels each rotatable on "a stationary shaft; means rotating each block wheel by the rotation of its respective clutch shaft; a block rotatable on each stationary shaft; means for rotating each block by the rotation of its respective block wheel, means for adjusting the relative position of each block and block wheel, consisting of a'lever on each block, cords running from said block levers through pulleys on the circumferemre of the block wheels to a common point in alinement with the block shafts respectively, continuing through said points to connections within reach of the operator; electric terminals in two sets on each block, circuits including said terminals, the electro-magnets of said respective clutches and said source of electrical energy; and means for connecting either set of terminals 10 on each block by one movable conductor for each block influenced by the force of gravity.

DIGHTON B. ELLSWO'RTH. \Nitnesses:

MILDRED S. Pownus, Rosoon C. NELSON. 

